From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: [RFT] kvm with Windows optimization Date: Thu, 25 Oct 2007 13:27:47 -0500 Message-ID: <4720E023.8050804@codemonkey.ws> References: <4720D122.4070606@qumranet.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel To: Avi Kivity Return-path: In-Reply-To: <4720D122.4070606-atKUWr5tajBWk0Htik3J/w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org Avi Kivity wrote: > This is a request for testing of an experimental kvm feature that > dramatically accelerates some Windows releases (when running with the > ACPI HAL, and especially with guest SMP). The feature detects accesses > by the guest to the Task Priority Register (TPR) and patches them at > runtime to a kvm-friendly code snipped that is provided by the BIOS. > > The upshot of all that is that > http://kvm.qumranet.com/kvmwiki/Windows_ACPI_Workaround is no longer > required, and Windows SMP no longer runs like a dog; it's quite snappy > from my very limited testing. > > Please download the test release from > http://people.qumranet.com/avi/tpr-opt-1.tar.gz and give it a spin. > Once it has received some exposure, I'll merge it into mainline. > > Credit for the original idea is due to Ben Serebrin. > BTW, is it wise to enable this by default for all guests? Ignoring the fact that we're modifying guest's memory without its knowledge, if a guest unmaps the VA mappings for the BIOS then all sorts of problems could occur. Regards, Anthony Liguori ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/